Network-attached storage keeps an eye on your stuff

Look Sharp

Take advantage of the low watt per operation compute power offered by modern NAS to monitor your cameras.

Modern off-the-shelf NAS hardware often has a CPU buried in it that offers great computing performance per watt. Many of these units require less than 10 watts to operate with a gigabit network link-up and the CPU at 100 percent use. A low-power-consumption NAS might consume 10 to 20 percent of the electricity that desktop hardware would need to run. The primary question then becomes: Is the CPU in the NAS “fast enough” to monitor one or more cameras and detect motion when it occurs?

In this article, I examine whether the QNAP TS-219P II, with a 2GHz Marvell ARM CPU and 512MB of RAM, is up to the challenge of real-time motion detection (Figure 1). Note that much of the article should also be directly applicable to its cheaper single-bay cousin, the QNAP TS-119P II, which sports the same CPU/ RAM.

The motion detector software, Motion, monitors the video signal from one or multiple cameras and is able to detect whether a significant part of the picture has changed, record and track movement, or launch arbitrary external commands to trigger other actions.

The new PiCam camera for the Raspberry Pi delivers image data with very little overhead, making it ideal for video surveillance applications. We find the bumps in the road you'll encounter and show you how to smooth them out with a few Linux commands and pipes.